厌氧消化污泥化学组成及其环境化学性质

THE COMPOSITION AND CHARACTERISTICS OF ANAEROBICALLY DIGESTED SLUDGE

本文剖析了厌氧消化污泥主要组成分的特征和污泥的农业利用价值。认为厌氧消化污泥含较多的有机质和N、P等养分，且有机态养分中相当部分容易矿化，因此具有很好的肥料价值。污泥中所含的各种重金属是一般土壤的20～40倍，但基本未超过我国污泥农用污染物控制标准。Cd和Zn，在污泥中主要以水溶态、交换态和松结合有机态存在，活性相对较高。此外，污泥也具明显的生物毒性。

The composition and characteritics of anaerobically digested sewage sludge. obtainedfrom Jizhuangzi Sewage Treatment Plant in Tianjing. were studied to evalute utilizationpotential of sewage sludge applied to cropland. The results showed that the sewagesludge was rich in organic matter, nitrogen. and phosphrous and that the ratio ofinorganic N to total N was higher in digested sewage sludge than that in undigestedone. Besides, the proportion of NH.+ to NO3 was also much higher in the former thanthat in the latter. Water soluble organic matter. protein, and hemicellulose accounted for57% of total organic matter in the sewage sludge. Concentrations of heavy metals ormetalloid (Cd, Ph, Hg, As. Cr, Ni, Cu, Znj in the sludge were about 2O--40 times higherthan those in the local uncontaminated surface soil. Cd and Zn exhibited higherchemical mobility because they existed mainly in the forms of exchangeable and weaklybound to organic matter.